atom - ✔✔ correct answer -composes all mass
-mostly empty space
nucleus - ✔✔ correct answer -10^-10 angstrong radius
-consists of protons and neutrons (together nucleons)
-particles equal in size and mass
-held together by strong nuclear forces
-stability measured by binding energy
binding energy - ✔✔ correct answer -energy required to break nucleus into individual particles
electrons - ✔✔ correct answer -1 to 3 angstrom from nucleus
-mass 1800x smaller than nucleon
electronic charge - ✔✔ correct answer -charge of proton or electron written in electron units (e)
-1 e = 1.6 x 10^-19 coulombs
-atom neutral when same number of protons and electrons
element - ✔✔ correct answer -building blocks of compounds, cannot be decomposed any further
atomic number - ✔✔ correct answer -number of protons
mass number - ✔✔ correct answer -number of protons plus neutrons
-approx equal to atomic weight (molar mass) units: amu
isotopes - ✔✔ correct answer -2 or more atoms of same element that contain different numbers of
neutrons
-nucleus is nuclide
hydrogen isotopes - ✔✔ correct answer -protium (H1)
-deuterium (H2)
, Introduction to General Chemistry
-tritium (H3)
ion - ✔✔ correct answer -atom carries charge
cations - ✔✔ correct answer -positive (fewer electrons than protons)
-smaller than neutral
-less repulsive force between e-
anions - ✔✔ correct answer -negative (more electrons than protons)
-larger than neutral
-more repulsive force between e-
salt - ✔✔ correct answer -neutral compound composed of positive and negative ions
period - ✔✔ correct answer -horizontal row
groups/families - ✔✔ correct answer -vertical columns
metals - ✔✔ correct answer -large atoms that lose electrons to form positive ions and positive
oxidative states
-"sea of electrons"
-ductile (stretch), malleable, thermal/electric conductivity, luster
-all solid at room temp except mercury
nonmetals - ✔✔ correct answer -form molecular substances (form covalent bonds)
-lower melting points
-form anions
metalloids - ✔✔ correct answer -some metal some nonmetal properties
representative elements - ✔✔ correct answer -groups 1,2,13-18